"You need to sleep 8 hours." Is that really true? The answer is: mostly yes. However, 8 hours is just an average for all adults, not an individual target. Some people do well with 6 hours, others need 9. And the number of hours is only half the truth anyway. What really matters is the quality of those hours.
Sleep Recommendations by Age
The National Sleep Foundation publishes these internationally recognized guidelines:
| Age Group | Recommended Sleep per Night |
|---|---|
| Infants (4 to 11 months) | 12 to 15 hours |
| Toddlers (1 to 2 years) | 11 to 14 hours |
| School-aged children (6 to 13 years) | 9 to 11 hours |
| Teenagers (14 to 17 years) | 8 to 10 hours |
| Adults (18 to 64 years) | 7 to 9 hours |
| Seniors (65+ years) | 7 to 8 hours |
Important: these are guidelines with individual tolerance. If someone feels refreshed and focused after 6.5 hours, they don't have sleep deprivation, even if the table suggests 7 hours.
Why Quality is More Important Than Duration
10 hours on a worn-out mattress are less restful than 7 hours on an ergonomic one. The reason: true regeneration only occurs during deep sleep phases. Growth hormones are released, muscles repair themselves, and the brain organizes memories. Those who constantly wake up due to tension or pressure points don't even reach deep sleep phases.
In other words: 8 hours of bed time minus 90 minutes of waking periods equals 6.5 hours of actual sleep. If only 30% of that is deep sleep, that's a good 2 hours of regenerative sleep. Not enough.
Sleep Phases Briefly Explained
A sleep phase lasts about 90 minutes. You go through 4 to 6 of these each night, each with:
- Light Sleep: Transitional phase, easy to wake up from
- Deep Sleep: Physical recovery, muscle regeneration
- REM Sleep: Dreams, mental processing
Deep sleep is strongest in the first 3 to 4 hours of the night. REM increases towards morning. Those who regularly wake up before the alarm and feel groggy often lose REM sleep, which can affect concentration throughout the day.
Athletes Need More Sleep
Those who train hard need more sleep, and especially more deep sleep. During this phase, the growth hormone HGH is released, which is responsible for muscle regeneration. Studies on athletes show that even 30 minutes of additional sleep can measurably improve reaction time, strength performance, and recovery speed. Learn more in our separate article How to sustainably improve your recovery.
How to Tell If You're Getting Enough Sleep
Honest indicators, no app needed:
- You wake up before the alarm, feeling awake
- No afternoon slump between 1 PM and 3 PM
- You don't need espresso to think clearly
- Not tired during long drives in the car
- Concentration lasts throughout the entire workday
If three of these points are regularly not true, you are sleeping too little. Either too short or too restlessly.
What Your Mattress Has To Do With It
If you're theoretically in bed for 8 hours and still wake up tired, it's rarely about the number of hours. More often, it's about sleep quality. A mattress that doesn't support your back robs you of deep sleep. You don't fully wake up, but your body can't enter the regenerative phase. You don't feel this directly at night, but in the morning and at midday.
If you've been tired for weeks despite spending enough hours in bed, the mattress is one of the first things you should check. An ergonomic 7-zone mattress with the right firmness can measurably improve deep sleep percentages. See also Which mattress for back pain.
When to See a Doctor
If it regularly takes you longer than 30 minutes to fall asleep, you wake up more than twice a night and can't get back to sleep, you snore, and you nod off uncontrollably during the day, then it needs medical clarification. Sleep apnea and insomnia can be treated well, but not with a new mattress. A new mattress won't help here. What helps: a sleep clinic appointment.
Risk-Free Testing to See If Your Mattress is Robbing You of Sleep
If you wake up feeling drained after 8 hours in bed, it's time for a test. At BeSports, you can test any mattress at home for 30 nights. That's 30 nights of real comparison, not a 5-minute lie-down test in a furniture store.
